Method of and apparatus for feeding web material



May 7, 1940.

METHOD D. E. MAXFIELD 2.199.708

OF AND APPARATUS FOR FEEDING WEB MATERIAL Filed Ilay 4, 1958 7Sheets-Sheet l ATTORNEY.

May 7, 1940- D. E. MAXFIELD METHOD OF AND APPARATUS FQR' FEEDING WEBMATERIAL Filed May 4, 1938 '7 Sheets-Sheet 2 INVENTOR. WD.- M M 9 2211/ATTORNEY.

y 7, 1940- D. E. MAXFIELD 2.199.708

METHOD OF AND APPARATUS FOR FEEDING' WEB MATERIAL Filed May 4, 193a 7Sheets-Sheet s R Qw Em PE W R ,wsmw v ow, I .whm W WEN m o: 3% wm 3fl\D. E. MAXFIELD 2.199.708

METHOD OF AND APPARATUS FOR FEEDING WEB MATERIAL May 7, 1940.

"7 Sheets-Sheet 4 Filed May 4, 1938 S3 0 mrwow R m vdhh em 2366 msow n33m I I 8 w o mlllfi 6 n .Qw II @N w G A y 7, 1940- D. E. MAXF IELD2.199.708

METHOD OF AND APPARATUS FOR FEEDING WEB MATERIAL Filed May 4, 1938 7Sheets-Sheet 5 May 7, 1940- D. E. MAXFIELD METHOD OF AND APPARATUS FORFEEDING WEB MATERIAL Filed May 4, 1938 '7 Sheets-Sheet 6 0 o 5% @m Sm y7, 1940- D. E. MAXFIELD 2.199.708

METHOD OF AND APPARATUS FOR FEEDING WEB MATERIAL Filed lay 4, 1938 7Sheets-Sheet 7 151 7 o 55 1/- 76A 72A 152 Patented May 7, 1940 a'rnon orAND arraas'ms i on manmo WEB MATERIAL Daniel E. Maxfleld, Philadelphia,Pa., auignor to Stokes and Smith Company, Philadelphia, Pa a corporationof Pennsylvania Application May 4, 1938, Serial No. 205,937

16 Claims.

cord with nor in response to the spacing between any particular controlelements on the web. nor in accord with the arrival of any particularcontrol element at any particular position, but by adjusting theeffective length of linear feed of the web by a series of very small andpreferably equal increments or decrements of predetermined magnitude sothat the operation of registry or positioning of the web ischaracterized by webfeeding movements either increasing or decreasing inlength, but neverthelesseach increment or decrement does not, except byoccasional coincidence, precisely correct the web-feeding movement butdoes always correct the movement in the right direction, shortening itwhen it is too long and lengthening it when too short, all. the timehunting the average spacing of the control elements on the web; toobtain substantially similar location on the containers of printing,decorations, or the like, generically termed designs, recurrentlyappearing on the web material.

In accordance with one form of my invention, exemplified by Figs. 1-10,the extent to. which the web is advanced for different feeding movementsthereof is varied, in accordance with responses of the detector, bychanging the time of exemplified by Figs. 17-20, the extent of for-'ward or efiective feed of the web is predetermined by controlling thetime of closure upon the web of the gripper mechanism during each returnstroke thereof.

My invention further resides in the methods and in the features ofconstruction and arrangement'hereinafter described and claimed.

For an understanding of my invention and for illustration of variousembodiments thereof, reference is to be had to the accompanying drawingsin which:

Fig. 1 is a front elevational view of a'packaging machine with partsomitted and parts broken away;

Fig. 2 is a plan view of web-clamping mechanism shown in Fig. 1;

Fig. 3 is a plan view of web-severing mechanism shown in Fig.andcorresponding with a similar mechanism shown in Fig. 1;

Fig. 4 is a plan view of parts appearing in Fig. 5 and correspondingwith similar parts shown in Fig. 1;

Fig. 5 is an end elevational view of the packaging machine of Fig. 1with parts omitted and parts broken away; 4

Fig. 5a is a face. view, on enlarged scale, of one of the webs shown inFig. 1; Y

Fig. 8 is a detail view of a modification of parts shown in Figs; 1 and5;

Fig. 7 is a front elevational view, on enlarged scale, of adjustablecontrol means for mecha nisms of Figs. 2 and 3 Fig. 8 is anendelevational view of parts appearing in Fig. 7; s

Fig. 9 diagrammatically illustrates an electric circuit for control ofmechanism shown in Figs. 7 and 8;

Fig. 10 is a timing chart referred to in explanation of the operation ofthe mechanism of Figs. 7 and 8;

Fig. 11 in perspective discloses the signiflcan elements of amodification of the packaging machine of Fig. 1;

Fig. 12 is a front elevational view on enlarged scale of parts appearingin Fig. 11;

Fig. 13 is an end elevational view of parts appearing in Fig. 12;

Fig. 14 is a plan view of parts appearing in Fig. 11;

Figs. 15 and 16 are diagrams referred to in explanation of theconstruction of cam means shown in Figs. '12 and 13;

Fig. 17 is a front elevational view of significant elements of stillanother modification of the packaging machine of Fig. 1;

Fig. 18 is a plan view, partly in section, of webengaging mechanism ofFig. 17;

Fig. 19 is a front elevational view of parts appearing in Fig. 18; and

Fig. 20 is an end elevational pearing in Fig. 1'7.

Referring to Figs. 1 and 5, the packaging machine there disclosed issuited to join the margins of webs of material thus to form tubes, eachof which is transversely flattened and sealed at intervalslongitudinally of the tube to form packages each of which is filledwhile still attached to the web, and is thereafter detached from the webby severance of the web material through a sealing section joiningadjacent packages. In general, the machine is of the type disclosed inUnited States Zwoyer Patent #1,986,422.

Referring to Figs. 1 and 5, the motor i mounted upon the shelf 2extending between the legs 3 of the machine, drives the main shaft 4through pulley 5 on the motor shaft, belt 8 which passes view of partsapover pulley 5 and the pulley I on the jack shaft 8, supported as bybrackets 9, II] from shelf 2, and sprocket II, on shaft 6, connected bya chain I2 to the sprocket I3 on shaft -4. The turret I4 at the top ofthe machine which, by means of measuring tubes 36, feeds thematerialwith which the packages are to be filled from the hopper or supply ductI5 to the filling tubes I6 and I6A, is continuously driven from shaft 4by the train of mechanism comprising sprocket II on shaft 4, chain I8,sprocket I9 on jack shaft 20, sprocket 2i on shaft 26, chain,22,sprocket 23 on shaft 24 supported, as by brackets 25, 26 from the framemember 21 of the machine, pinion 26, on shaft 24, which engages thebevel gear 29 on the vertical shaft 30 which extends through and beyondthe frame member 3| and to whose upper end is secured the sprocket 32connected by chain 33 to sprocket 34 on shaft 36 to which is secured theturret head or plate I4.

From the under side of the turret plate I4 there extend a plurality ofcylinders or measuring tubes 36 each in register with openings throughplate I4 to receive a charge of material as it passes beneath the openend of the 'stationary supply hopper I 5 or equivalent. The plate 31,suitably secured as by brackets 38 to the frame member 3| of themachine, serves to close the open bottoms of the cylinders 36 as theyrevolve with the turret head I4 except when each, in turn, passes overopenings in plate 31 which are in register with the filling tubes I6 or"A.

During each cycle of the package-forming mechanism hereinafterdescribed, a pair of tubes 36 pass over and discharge their contentsinto the filling tubes, and thereafter pass beneath the hopper I5 forrefilling.

From the rear of the upright frame members 39 of the machine thereextend the U-shaped bearing members 40 for receiving a bar or rod Hwhich supports the rolls or reels R, RI of packaging material, which,for purposes of explanation, is assumed to be moisture-proof Cellophane,Pliofilm, or other material consisting of, impregnated with, orotherwise surfaced with a material which is adhesive or plastic whensubjected to heat.

The web WI from roll RI, Fig. 5, is threaded through the machine to passbeneath the idler bar or roll 42, thence upwardly between the elementsof a registration-detector DA, hereinafter more fully described, thenceover and under the tensioning rolls 43A, A on the spring-biased arm 45A(biasing spring not shown) pivotally mounted upon the extension 46A offrame member 39. and then upwardly and over the spreader 41A. Beyond thespreader web WI is formed into a tube TA about the filling tube I6A bythe forming tool 48A attached to the bracket 49A which is adjustablysecured to the bar 50A (Fig. 1) extending downwardly from the framemember 3|.

The web W from the other roll R of packaging material is similarlythreaded through the machine and is formed into a tube T about thefilling tube I6; the elements for guiding and forming web W areidentified in Fig. 1 by the same reference characters, but with omissionof the suffix A", utilized to identify the corresponding elementsassociated with web.Wl.

The forming tools 48, 48A, which may be of construction more clearlyshown in the aforesaid Zwoyer Patent #1,986,422-, each shapes theassociated web into the form of a tube and also effects overlap of theweb margins at the front of the filling tubes I6, I6A. The margins ofeach web are joined by application of heat and pressure to form a closedtube; specifically, the overlapping margins of web W are pressedtogether by the roll 6| in the core of which are disposed several turnsof wire electrically heated so as to raise roll II to temperaturesumcient to soften the thermo-plastic or adhesive material of theoverlapping web margins and so effect their union.

The roll 6IA, Fig. 5, similarly operates upon the margins of the web WIto form a closed or circumferentially continuous tube of web materialabout the filling tube I6A. The sealing rolls 6i, BIA are respectivelymounted upon shafts 62, 62A individually supported by the frames 63, 63Apivotally mounted for angular movement in a horizontal plane upon therod 54 extending downwardly from the frame member 3! of the machine.

During each cycle of the machine, the webs W, WI are individuallyflattened below the lower ends of their respective filling tubes, andare drawn downwardly, by heated clamping tools G, GA which seal thetubes of web material transversely thus to form containers closed attheir lower ends but whose upper ends are open and in communication withthe filling tubes I6, I6A for filling purposes. The feeding movement ofeach web also brings a previously formed package beyond a knifemechanism, hereinafter described, which cuts the web to detach a filledand sealed package from the web material. A brake member, such aspivoted member B, Fig. 5, prevents the inertia of each roll of webmaterial from producing slack in the web material fed therefrom.

Because the mechanisms for feeding the Webs W,,WI and for severing themto form individual packages are substantially identical, it is necessaryspecifically to describe only the mechanism for feeding and cutting oneof the webs; the corresponding elements of the feeding and cuttingmechanisms for the two webs will be identified by the same referencecharacters but the mechanism associated with the web WI will have addedthereto the sufiix A.

Upon the main shaft 4 is mounted the cam 55 which effects reciprocationof the web-grippers G, GA downwardly from and back to their broken linepositions indicated in Fig. l. The periphery of cam is engaged by theroller 56 on pin 51 which extends from the yoke member 58 whose forkedend straddles shaft 4 and which is connected by bar 69 to one arm 60 ofa bell crank lever pivoted at 6| to bracket 62 secured to the under sideof the frame member 21. The other arm 63 of the bell crank lever isslotted adjustably to receive the supporting stud for a roller 64 whichengages the under side of the horizontal extension 66 of member 66adjustably secured as by the bolts 61 to the plunger 68 whose lower endpasses through the bearing 62a afforded by bracket 62, and whose upperend passes beyond the top of the table or frame member 21. Attached toor integral with the upper end of the plunger 68 is a cross arm 69 whoseopposite ends provide bearings for the lower ends of the shafts 10, 10Awhich extend through the web-gripping devices G, GA. The shafts II, IIAextending parallel to and closely adjacent the shafts I0, 10Arespectively pass through the crossmember 69 and the top 21 of themachine frame; the upper ends of the shafts III, II and 16A, IIA passjaiaaros through and are guidedby the frame member SI.

pins "A, "A extendingthrough member "A and attached to member "A. .Whenthe shafts 14A and HA are in the angular position shown in 2, thesprings 14A, "A are effective to hold the corrugated, web-engaging jaws"A, "A

in clamping engagement with web WI. The jaws 18A, "A are heated,preferably electrically. as in aforesaid Zwoyer patent, to soften thethermoplastic or adhesive surface of the web and so form, during theirclamping engagement with the tube TA, a flattened sealing sectionextending transversely thereof. 1

when the shafts 10A and "A are concurrently moved in the same directionthrough a substantial angle, as hereinafterdescribed, the cam members"A, BIA secured respectively to shafts IIIA and I IA eil'ect separationof the gripper jaws and so release the web or tube TA.

The under surface of gripper members 12A. 83A engage the spacer members"A, "A supported respectvely by the sprockets 84A, "A on the shafts 10A,HA. The upper surfaces of the gripper members are engaged by the flangedmembersBGA, 81A suitably secured to shafts HA and MA. The sprockets 85Aand v84A are connected by chain 88A to effect rotation of the shafts inunison when one of them is actuated as hereinafter described.

The shafts If! and II support the similar webclamping device G whosejaws are moved toward and from web-clamping position by'angularmovements of the shafts M, II.

During rotation of shaft 6 the cam 55 effects reciprocation of the crossmember 89 to effect vertical reciprocation of the two web-clampingdevices G, GA. Substantially at the top of the stroke of the crossmember 68, the shafts II and i 5A are rotated as hereinafter describedto effect closure of the jaws of the two grippers G, GA so that duringtheir downward movement both webs are pulled downwardly with respect totheir associated filling tubes I6, 86A. The flattening and sealingaction of grippers G, GA completes the sealing of a pair of filledcontainers and seals the bottom of a pair of containers whose upper endsare open for filling through tubes i8, IEA.

Before the cross arm 69 reaches the bottom of its stroke, theweb-feeding devices G, GA are individually controlled, as hereinafterdescribed, to release the webs W, WI y The length of the stroke of thecross member t9 and the parts movable therewith is adjustable to suitthe machine for making packages of different lengths. Referring to Fig.5, when the roll 64 is clamped near the outer end of the slot in theoscillatory arm 68,

the vertical stroke of the cross member .69 which carries the grippersG, GA is substantially longer than when the adjusted position of roller64 on the slotted arm 63is nearerthe pivot GI. With the arrangementshown in Fig. 5, a change in position of roller 64 with respect to theaxis of rotation of the lever arm 63 not only changes the length of thestroke of member 69 but also affects its position at the bottom of itsstroke; the shorter the stroke, the higher the lowermost position ofcross-arm 69 unless member 66 on plunger 68 is readjusted. By recourseto the construction 'showninl'lmmtbe without change of the position 1 IIat the bottom of its stroke.

the modification will become more apparent after subsequent descriptionof the severance of the a length'fof stroke may be varledtosuit-different lengths of the package of the cross arm The advantage ofwebs to detach packages therefrom.

In the construction shown in Fig. 6, the slot lb, instead of beingradial like the slot 63A, Fig.

5, is substantially parallel to the end face of the.

at the bottom member ll when plunger 80 is of its stroke; therefore,adjustment of roller 04 to various positions along slot 63b to obtainvarious lengths of stroke of the plunger 68 does not change thelowermost position of the plunger or of the grippers G, GA movabletherewith.

The opening and closing movements of the' gripper mechanism G arecontrolled by barrel cam 89, Fig. 1, rotatable with shaft 90 driven frommain shaft 4 of the machine by the bevel gears SI, 92 secured,respectively, to shaft 4 and shaft 90. The periphery of cam 89continuously en- .gages the roller, 93 at the lower end of thevertically reciprocable member 94 whose upper end is pivoted to one armof a bell-crank lever 95 supported by bracket 96 on the upper surface ofthe table member 21 of the machine. The other arm of the bell-cranklever is connected by link 91 to the rack member 98 slidable within aguide member 99 attached toor integral with the frame member 39 of themachine. The rack 88 is continuously in mesh with the elongated gear Iattached to shaft II. Throughout the vertical reciprocation of thegripper frame 69, the gear I00 remains in engagement with the rack inorder that cam 89 may effect opening and closing of the gripper jaws atdesired times in a cycle of reciprocation of the gripper.

Similarly, the cam 89A through the bell-crank lever 95A and rack 98Aeffects rotation of gear IBOA at different times in the cycle ofrotation of gripper frame 89 to effect opening and closing movements ofthe gripper GA.

The hell-crank levers 95, 95A are biased, as by the springs IbI, IIIIA,to maintain engagement of the cam followers 93, 93A with cams 89, 89Arespectively.

The motion of theracks 98, 98A is also utilized to efl'ect operation ofthe knife mechanisms K, KA which sever the completed packages from thewebbing; rack 98A, in addition to maintaining continuous engagement withgear MA on the reciprocable gripper frame, is continuously in mesh withgear IMA, Fig. .4, on shaft IMA, whose upper end is received by abearing in the extension 604, Fig. 5, of the standard I which issuitably attached to the top of frame member 21 near the front of themachine. Gear IIJZA is continuously in engagement with gear I USA onshaft WIA extending parallel to shaft I03A and whose lower end isreceived by a bearing in the frame member 21. Above gear IDSA, Fig. 5,

' shaft IIIIA extends through the standard extension I04 and through,the web-cutting mechanism KA which comprises two knives I08A and 109Aguided for reciprocation in a horizontal plane by the structure IIIIA.The gear I I IA on shaft IDIA engages a rack integral or attached to theupper blade I08A and'gear II2A, also on shaft III'IA, engages a rack onthe opposite side of the lower blade INA. Therefore, for rotation of theshaft io'lA'in one direction the upper and lower knives move toward eachother to sever web WI and for reverse rotation of shaft IIllA the knivesmove from their web-severing position. As more clearly appears in Fig.3, the web WI passes downwardly through an aperture defined by thecutting or shearing edge at the forward end ofthe lowerblade NBA and thecutting or shearing edge of the upper blade IOBA. Consequently, as shaftIIlIA, Fig. 3, rotates in clockwise direction, both blades move towardthe cutting line" X-X, Fig. 3, to sever the web WI. The mechanism forcutting the web W is similar and the corresponding parts are identifiedby the same reference characters with omission of the suflix A.

The two cutting heads K and KA are carried by a common member I38adjustably secured to the standard I05 as by the bolt I39 which extendsthrough an elongated slot in member I38. As indicated in Fig. 5, thecutting heads are adjustable in unison by the hand wheel H3 at the lowerend of a threaded shaft II which extends through the stationary framemember 21 and is threadably received by the extension II5 of the supportI38 for the two cutting heads.

Provision for vertical adjustment of the cutting heads is not necessarywhen there is utilized the modified arrangement shown in Fig. 6, which,as previously explained, insures that the frame 6!! always has adefinite lower position regardless of the adjustment of roller 64 toprocure different lengths of package by adjustment of the stroke offrame 69. I

As thus far described, the cams 55, 89 and 89A make one revolution percycle of the machine; the'cam effects, during one revolution thereof,one upward and downward stroke of the gripper frame 69; and during onerevolution of cams 89, 89A, the grippers are opened and closed, and theknives are closed and opened. As hereinafter more fully described, thewebs W and WI are fed during the downward movement of the gripper frame69, and at or somewhat before the end of the downward movement of thegrippers their jaws are opened to release the webs and the knives severthe webs to detach completed packages which are discharged from themachine by chutes II6, IISA.

The webs W and WI are often provided with recurrent printing ordecorative matter which it is desired shall appear in the individualpackages at a definite position similar for all of packages. For variousreasons, such as the effect of atmospheric conditions upon the webmaterial during the printing or while in the packaging machine, it isordinarily not possible to attain exact or substantially exactregistration of the printing or decorative matter, exemplified in Fig.5A, as appearing upon the individual packages, by forming or cutting allpackages to exactly the same length.

In the packaging machine shown in Figs. 1-9, there are provideddetectors D, DA for inspecting the registration of the printed matter ordesign on the webs and for advancing or retarding the gripper openingand web-severing operations effected in the next cycle of the machine,thus to correct for inaccuracies of register of the recurrent designs.or equivalent as they appear on the web and so avoid cumulation ofvariations in the spacing between the designs.

In Figs. '7 and 8 there is disclosed a control mechanism responsive todetector DA for shifting the timing of the gripper GA and of the cuttingmechanism KA in the cycle of reciprocation of plunger 68; it is to beunderstood a similar mechanism is utilized to vary the timing of themachine.

tion detector D (not shown). The cam "A is slidably keyed to shaft. A,Figs. 7 and 8, and is provided with a grooved collar II'IA for receivingrollers carried by the yoke USA at the upper end of arm II9A pivotedintermediate its ends on the bracket I2IJA attached to the frame I Thelower forked ends I2IA of the lever IIQA embrace pins I22A extendingfrom the member I 23A threadably received by the shaft IflA whose endsare supported respectively by aforesaid bracket I2IIA and bracket I25A.To shaft I24A are attached the spaced ratchet members IIBA, I2'IA. Thebell-crank lever I28A mounted upon shaft INA for angular reciprocationwith respect thereto is provided at its upper end with a roller I29A forengaging the groove I3IIA of cam member I3IA secured to shaft 90. Thecam groove is so cut and the cam is so positioned on shaft A that whilethe web-feeding plunger 68 is at rest, and therefore while the webs Wand WI are stationary, the bell-crank lever I "A is swung toward andfrom the position shown in Fig. '7 to effect rotation of shaft I'MA inone direction or the other by engagement of one or the other of pawlsI32A, I33A, carried by the lower arm of thebell-crank lever I28A withratchet I26A or ratchet I2IA. The arm I34A, secured to the same shaft towhich the pawls I32A and I33A are attached, is connected at its lowerend, as by link I35A, to the core or armature I3IiA of a solenoid orequivalent electromagnetic device I3IA. The spring i38A compressedbetween the pawl I32A and the block I39A rotatably mounted in thestationary support I 40A biases the pawl I 32A into engagement with theratchet IZIA, and concurrently biases the pawl I33A out of engagementwith ratchet I2'IA;' therefore, if solenoid I 31A is not energizedduring the aforesaid to and fr movement of the bell-crank lever I28A,the sit-aft INA is moved in counterclockwise direction, Fig. '7, duringthe return stroke of the bell-crank lever to the position of Fig. 7. If,on the other hand, the solenoid I3'IA is energized during the angularreciprocation of the bell-crank lever, the pawl I33A is pulled by coreI36A to engage the ratchet I2IA, and during the forward stroke of thebellcrank lever from the position of Fig. '7 effects rotation of theshaft I24A in clockwise direction, Fig. 7.

Upon each of the webs W, WI is a series of opaque spots or marks 0 eachhaving the same position with respect to printed or other matter on theweb which is to appear in the packages successively cut therefrom; thespacing between adjacent spots, therefore, corresponds to the nominalaverage length of the packages to be cut from that web. The marks orcontrol elements 0 may be part of the designs or printing on the web orthey may be in addition thereto and, in any event, they possess adistinguishing characteristic suited for the selected type of detector;in the particulararrangements herein disclosed; the light transmissioncharacteristic of the registration marks is different from that ofadjacent yveb portions; for another type of detector, the controlelements 0 may be of electrical conductivity difierent from that ofadjacent web portions;1 for example, they may be dabs or strips ofconductive substance or, less desirably, perforations in the web; in allmodifications the detector observes the web while stationary.

Whether or not the solenoid I3IA is energized or deenergized at thatportion of each cycle of as an electrically heated resistor, anddirected toward a radiation responsive device CA such as a photo-cell,thermocouple, or the like. The photo-cell CA and lamp LA, Figs. 5 and 9,are preferably disposed in individual housings which areclosed exceptfor narrow slits in alignment with each other and between which the webWI passes. The radiation may be concentrated by a suitable opticalsystem comprising one or more mirrors or lenses. If the web WI at theend of a feeding stroke comes to rest with an opaque spot 0, inalignment with the slots or apertures in the two housings, thephoto-cell does not receive radiation from the transmitter lamp LA orequivalent and, consequently, in the particular system disclosed thesolenoid I8IA is not energized with the result the shaft I A duringoscillation of arm I28A is moved in counterclockwise direction to movecam 89A to the right with respect to the position shown in Fig. 8.Because of the shape of the cam, which is hereinafter described, theresult of this change in position is to effect release of the web andseverance thereof earlier than before in the next downward stroke of thegripper frame with the results that the package severed from the web isslightly shorter than the preceding package and that a succeeding opaquespot on the web may to greater or lesser extent intercept the path ofthe radiation from LA to CA. For every subsequent cycle of the machine,the time of release of the grippers will be still further advanced,still further reducing the distance between successively formed seals,until, when the web comes to rest at the end of a feeding stroke, thebeam from the lamp LI is not obscured or is sufilciently less obscuredby one of the series of registration marks or control elements on theweb. Thereupon'the solenoid I8'IA is energized during the oscillation ofthe bell-crank lever I28A with the result that the shaft I24A is rotatedin clockwise direction to move cam-89A. to. the left along shaft 88A andtherefore effect release of the grippers and websevering movement of theknives of cutting head KA later in the downward stroke of plunger 88with the result the distance between successively formed seals isincreased and the package cut in the subsequent cycle of the machine isslightly longer than before; and for every subsequent cycle of themachine, the time of release of the web by gripper GA is more and moreretarded still further increasing the distance between successivelyformed seals until eventually, when the web is at rest at the end of afeeding stroke, an opaque spot 0 on the web again intercepts sufficientradiation from LA to CA to cause deenergization of the solenoid I8'IA.

For every cycle of the machine, each of the webs W, WI is inspected byits respective registration detector D or DA and, in accordance with theposition of a registration index or control element 0 on each web, it ispredetermined whether in the next feeding stroke of the individual web.the time of release of the web from its feeding gripper'and the time ofoperation of its individual severing means is made to occur earlier orlater in the web-feeding stroke of plunger 68in effect to shift thelocation of the containers formed by the sealing operations of thegripper mechanism with respect to the designs on the web between theseals. Thus the proper positioning of the designs on the containers iseffected by control of the package-forming mechanism itself and not byany additional mechanism operating upon the web prior to package-formingoperations thereon, Although both grippers G and GI are carried by oneand the same reciprocating frame 69, the extents to which the webs W andWI are fed in any particular cycle of the machine may differ dependingupon the prior re-" sponses of the detectors D, DA indlvidualto thewebs; for example, the response of detectors D and DA while the webs Wand WI are concurrently stationary may be such that in the next downwardstroke of the gripper frame the extent of feed of web W is less than inthe prior cycle, whereas the extent of feed of web WI is vice remainsconstant for any given adjustment of cutting-head support I88.

In the particular packaging machine shown in Figs, 1-9, the cam 55 is soconstructed that, as appears from the timing diagram, Fig. 10, theplunger 68 is at rest in its uppermost position from about zero degreesto about 50 of the machine cycle; consequently, during that part of thecycle the webclamplng devices G, GA, are at rest in their dotted linepositions of Fig. 1. During that interval the cam followers 98, 93A ridefrom the high part of cams 89, 89A, respectively, allowing the springsIIiI, MA, to move the racks 98, 98A to the right, Fig. 1, to effectrotation of shaft I0, 'II, 10A and I IA, in such direction that the jawsof the clamping devices G, GA close upon the tubes T, TA of web materialbelow the lower ends of the filling tube I8, I8A, thus, as previouslydescribed, to seal the upper ends of filled packages and concurrently toform and close the bottoms of containers about to be filled; this samemovement of the racks 98, 98A, effects rotationof shafts I01. IIIIA, indirection to separate the knives of the two cutting heads K, KA, topermit the filled packages as yet unsevered from the web to pass betweenthe knives during the subsequent downward movement of the web-feedingdevices G, GA.

The downward movement of plunger 68 and therefore of the web-clampingdevices G, GA, begins at about 50 of the machine cycle and continues toabout 230 thereof; the length of the plunger stroke, and therefore themaximum possible extent of feed of the webs W, WI, depends upon thesettingof the member 64, as previously described.

Each of the barrel cams 89, 89A, is so constructed that during thedownward movementof the plunger 68 the cam followers 93, 99A rise fromthe low part of cams 88, 89A to the high part thereof to effect movementof the racks 98, 98A to'the left, Fig. 1, thus individually to effectrelease of the webs W, WI from the feeding devices G, GA; andsubstantially concurrently with release of each web the knife mechanismK or KA operated by the same rack which effects web release severs theweb to detachtherefrom a filled package. Although both webs W, WI areconcurrently clamped, the time at which each web is released and severedduring descent of the plunger it depends upon the response of theregistration-detecting device associated with that particular web, aspreviously herein described. For example, and again referring to Fig.10, when the responses of the registration detector D or DA have beensuch that the cam follower 93 is at the lower end of cam 89 as viewed inFig. 10, or cam follower 93A near the right edge of cam 98A as viewed inFig. 8, the cam follower 93 or BSA, as the case may he, meets the riseof the cam early in the downward stroke of the plunger, for example, atabout 105 of the machine cycle, thus to effect release of the web andseverance of the end package early in the downward movement of plunger68. To take the other extreme condition, when the prior responses of theregistration detector D or DA have been such that the cam follower 93 or93A is near the other edge of the associated cam 89 or 89A-upper extentof cam adjustment, Fig. 10-the cam follower does not meet the rise ofthe cam until about 225 of the machine cycle,

or just before the bottom limit of the downward stroke of the plunger80. For intermediate positions of cams 89, 89A, the times of release ofthe grippers G, GA and of the operations of cutting mechanisms K, KA arecorrespondingly predetermined. Thus, the extent of feed of each of thewebs W, WI, in a particular cycle of the machine,

depends upon the positions of the cams 89, 89A

with respect to cam followers 83, 93A which positions are subject toindividual control by the registration detectors D, DA.

Reverting to Fig. 10, the plunger-68 remains at its lowermost positionfor a brief time, for exampie, from about 230 to 240 of the machinecycle, and then returns at accelerated rate to its uppermost position infrom about 240 to 360 of the cycle. During the upward movement of theplunger, both sets of gripper jaws are open to clear the filledcontainers whose upper ends are to be closed by the next clampingmovement of the jaws.

In each cycle of the machine two packages are filled and two packagesare cut from the webs W, WI; although all packages cut from the webs areapproximately of the same length, each package from each of the webs isslightly longer or shorter than the immediately preceding or immediatelyfollowing package, and the length of a package cut from one web may beeither shorter, longer or equal to the package severed from the otherweb in the same cycle of the machine.

In the modification of my invention shown in Figs. 11-14, packages areformed from two webs of packaging material by mechanism similar to thatof Figs. l-9 and for convenience and brevity the corresponding elementsof both modifications are identified by the same reference characters.In the modification of Figs. 11-44, there are provided individualfeeding plungers for each of the web clamping devices G, GA and thelength of stroke of each of these feeding plungers is capable of beingadjusted independently of the other in accordance with the response ofits associated registration detector D or DA. Moreover, it is alsocharacteristic of the modification of Figs. 11-14, unlike themodification of Figs. 1 to 9, that the time at which each web isclamped, the time at which it is released, and the time at which it issevered all remain the same in all cycles of the machine and are thesame for both webs.

Referring to Fig. 11, the two racks 98, 98A of Fig. 1 are replaced by asingle rack 980 which engages the gear I00 which controls the openingand closing of the web-clamping device G'and also engages gear IIIOAwhich controls the opening and closure of the gripper GA; the movementsI of the rack 880 are controlled by a single nonadjustable cam 880 whichreplaces the two adjustable cams 89 and 89A of Fig. 1. The periphery ofthe cam 890 is incontinuous engagement with the cam follower 930 carriedby arm 940 pivotally connected to the bell-crank lever A connected bylink 91A to the aforesaid rack 880. The cam 890 is so cut that the jawsof the grippers G and GA close upon the respective webs W, WI bymovement ending at about 50 of the machine cycle and are concurrentlyopened near the bottom of the strokes of their respective plungers 880,680A which, in the particular construction shown, are at rest at thebottom of their stroke from about 230 to about 240 of the machine cycle.The rack 980 is also in mesh with gears I02, I02A, Fig. 14, foroperating the knives of the web-cutting heads K, KA, as in themodification of Figs. 149, so that concurrently with closing movement ofthe gripper jaws, both sets of knives open to avoid obstruction to thepackages about to be fed therebetween, and so that concurrently withopening of the grippers G, GA, the two sets of knives in the heads K,KA, are concurrently operated to sever packages from the webs W, WI.

With the webs W, WI are associated the individual registration detectorsD, DA, similar to those described in connection with Figs. 1-9, each ofwhich control the energization of an electromagnetic device such assolenoid I3IA which determines which of the pawls I32A, IRA, iseffective during an oscillation of the arm I28A which oscillation istimed to occur in each cycle of the machine while the webs arestationary. If solenoid I3IA is energized during oscillation of arm'I28A, the cam 550A is moved in one direction along shaft 400, and.conversely if the solenoid I3IA is not energized during oscillation ofarm I28A, the barrel cam 550A is moved in opposite direction axially ofits shaft. In like manner, the detector D controls the position of cam550 longitudinally of shaft 400. The control of the positions of each ofbarrel cams 550 and 560A of Fig. 11, in accordance with the alignment ormisalignment of successive opaque spots or control elements 0 on thewebs W, WI, is effected by an arrangement identical with that shown inFigs. 7 and 8 and previously explained. In the modification of Figs.11-14, the rotation or angular adjustment of shaft I24A is utilized toshift the position of cam 550A which, as will hereinafter appear,controls the stroke of the gripper GA, whereas, in the modification ofFigs. 1-9 the angular adjustment of shaft I24A controls the setting ofcam 89A to vary in a cycle of the machine the time of release of thejaws of the web-clamping mechanism GA.

Reverting to Figs. 11, 12 and 13, the periphery of cam 5250A is engagedby the cam follower 560 carried by-the rack member 590 which is in meshwith the gear sector 600 integral with or attached to the lever 630 towhose free end is connected the roller 84 for engagement with the undersurface of the member 66 suitably secured to the feeding plunger 680A.For each revolution of cam 550A the plunger 880A makes one completecycle of its vertical rectilinear reciprocation; therefore, for eachrevolution of the cam 550 the web-clamping device G moves to and fromits lowermost position from. which to the cutting plane of head KA thedistance is fixed or predetermined. The length of the stroke of each of7 tion detector associated with the web ample, is moved shown-in Fig.11, the

e pluns'emll fl, A dep nds. In e particular is moving upwsnllmbut theavenge crane. cycle or the machine, upon the axial adjustments plungerduring this part-oi a particularcycle deoi the came I", "0.6.. when com"IA, ior exto the right from its position plunger "IA, and therefore thefeed of the web WI, isincreased and conversely, when cam IIIIA is movedto the left of its position shown in Fig. 11, the stroke of plunger 0Ais shortened to (IE-'- crease. the length of package cut from the web.Although both sets of grippers G and GA open and close at thesame timein the cycle of the machine, the extent to which they feed theirrespective webs depends upon the settings of the cams 550, 555A. Thelength of stroke of each or the plungers 680, 580A is always eitherincreasing or decreasing, depending upon the responses of the associatedregistration detectors so to vary the distance between successivelyformed seals and thus shift the location of the containers formed by thesealing operations with respect to the designs between the seals. In theparticular. arrangement shown, the length of stroke of each or theplungers is'progressively increased for successive cycles of the machineuntil the registraobserves an opaque spot 0 on the web while stationaryat the end of a feeding stroke; thereupon, the length of stroke isincrementally decreased in the following cycles until, in a subsequentcycle, the registration detector is actuated by partial or completeabsence of a control element to effect energization of the solenoidassociated with stroke-controlling mechanism for that web, whereupon thelength of stroke is again increased.

The construction of cams 550 and 550A is best understood from. Figs. 12,13, 15 and 16. Because these cams are identical in construction, onlyone of them, cam 550A, needs to be specifically described. Cam 550Athroughout-its length within the angle between 223 and 240,corresponding to the bottom dwell of the plunger 580A, is of constantradius, thus insuring that regardless of the axial position of cam 550A.the lowermost position of the gripper device GA is always the same;otherwise stated, that segment of the cam corresponding to the portionof the machine cycle between 230 and 240 is a segment of a cylinder.Within the angle between 0 and 50 of the machine cycle for which theplunger 580A is at rest in its uppermost position, the radius of cam550A progressively decreases from the large end of the cam, Fig, 15, tothe small end of the cam, Fig. 16, thus providing 'for difierentuppermost positions of gripper device GA in accorda'ncewith therespouses of the detector DA; this segment of the 4 cam may therefore beconsidered as a segment of a truncated cone whose maximum radiusdetermines the maximum stroke of plunger 680A and whose minimum radiusdetermines the minimum stroke of the plunger. For each intermediateposition or cam 550A with respect to its follower 560, the stroke ofplunger 680A is'correspondingly predetermined within the aforesaidlimits. In the machine described, the ratio of the maximum to theminimum stroke is about two to one; specifically, the maximum stroke isabout 6" and the minimum stroke about 3".

From 50 to 230 of every machine cycle, the plunger 680' is movingdownwardly but the average speed at which the plunger moves downwardlyin a particular cycle depends upon the axial position of cam 550A withrespect to the cam follower 560 during that cycle. From 240 to 360 ofevery cycle of the machine, the plunger 585 length of more of thebrevity and clarity,

pends upon theaxisl position or cam "A with cam '50 are similaroridentical so that both grippers G. GA andboth knife mechanisms K, KAoperate concurrently in all cycles of the machine. But because of theindependence oi the axial positions or cams 550, "0A. the lengths of'the packages cut from the webs W, WI in any particular cycle of themachine may be and usually are difierent.

In the modification whose significant components are shown in Figs. 17to 20, the webWI, from which packages, labels or wrappers are to be out,is intermittently ted by a gripper mechanism having a constant length ofstroke, and proper registry of printed or other matter with respect tothe packages or wrappers cut from the web is maintained by shifting thetime at which the web is clamped by the gripper mechanism during itsreturn or non-feeding stroke. For elements having the same purpose orfunction as elements of the modification of Fig. 1 are identified by thesame reference characters.

For each revolution of cam 55, which rotates once for each cycle of themachine, the plunger 68 carrying the web-gripping mechanism GA makes onecycle of reciprocation. Thelength of stroke of the plunger, and mum feedof web WI for making packages or labels of desired average or nominallength, is predetermined by the setting of roller 65 in the slottedoscillatory arm 63.

For purpose of explanation of a specific embodiment of thismodification, it is assumed that the web WI is of Cellophane or othertransparent or translucent webbing material, and that the recurrentregistration marks or control elements 0 on the webbing are opaquespots.

In front of web WI, adjacent the uppermost position of the web-grippingdevice GA, indicated by dotted lines in Fig. 17, there is disposed atmirror MA or equivalent for reflecting light from. source LA to thephoto-cell CA or equivalent, under conditions hereinafter specified, asalso does shroud I45 which is to prevent straylight, other than fromlamp LA, actuating photo-cell CA. The shroud may either be fixed orreciprocable with the gripper structure GA. The lamp and photo-cell arecarried by and move with the gripper mechanism GA during itsreciprocation. There is also mounted upon or carried by the grippermechanism GA and electromagnet I3IA, Fig. 18, whose armature I36A isconnected by link I35A to a latch I50 whose hooked end engages the pinI5! on arm I52 to restrain the gripper jaws 18a, 190. out of engagementwith the web WI. When the solenoid I3IA is energized, latch I50 is movedin clockwise direction, as viewed in Fig. 18, to release the arm I52,whereupon the springs "A, ISA efiect closure of the gripper jaws uponthe web.

As the gripper mechanism GA approaches the lower limit of its feedingmovement, the adjustably fixed cam I53, Figs. 18 and 19, engages theroller I54 on arm I52, causing the arm to move in clockwise direction tothe position shown in Fig;

therefore the maxion shafts 10A, HA to release the web WI. This movementof arm I82 also permits the spring I" to rese the latch IIO-to theposition indicated in Fig. 8.

The gripper jaws remain open during the subsequent upward movement ofthe plunger 08 until radiation from the lamp LA or equivalent isreilected by the mirror MA into the photo-cell, whereupon theelectromagnet "1A is energized to efiect closure of the gripper Jawsupon the web, as above described. The mirror MA should be so locatedwith reference to the nominal normal position of the opaque spot as tooverlap it but not to extend below it. For any particular return strokeof the gripper mechanism GA, the time at which the photo-cell receiveslight from the lamp is dependent upon the position of opaque spot on thethen stationary web with respect tothe reflector MA. Because the web isgripped before the end of the return stroke, at least that part of itadjacent the grippers is reversely fed to an extent dependent upon theremaining distance to be travelled by the gripper in its return stroke;with the net result, the actual or forward feed of the web is less thanthe constant distance in the forward stroke for which the web remainsgripped by an amount corresponding with the variable distance, in theimmediately prior return stroke, for which the web was, in a sense,reversely fed. For example, if the lower edge of an opaque spot 0 isapproximately at the same level as the lower edge of the mirror, thegripper mechanism must return substantially to its uppermost positionbefore the mirror MA is capable of reflecting light from the lamp intothe photo-cell, and accordingly, under this circumstance, the amount ofwebbing fed or actually advanced by the gripper mechanism in its nextdownward stroke is appreciably greater than when, for example, the upperedge of an opaque spot 0 registers with the lower edge of the mirror, inwhich event the mirror reflects light to the photo-cell substantiallybefore the gripper mechanism. GA reaches its uppermost position. In thelatter case, the net result of the early closure of the grippermechanism during its return stroke is that of reduced extent of feed ofthe webin the next downward stroke of the gripper mechanism. Thesevering of the web may take place at or within the particular webspacing adjacent the opaque spot observed or at or within a web spacingremoved therefrom a predeter-= mined number of spacings.

The variations in the timing of the closure of the gripper mechanism arealways such as to maintain an approximately correct register of theprinted matter on the packages or wrappers out from the webbing byweb-severing mechanism generally similar to or identical withwebsevering mechanism KA of Fig. 1. The length of the opaque spot withthe web must obviously be greater than the maximum variations inthelength of web spacing.

If desired, the movement of the plunger 88 may, as in the modificationof Fig. 1, be utilized to effect feed of more than one web, and in suchcase, it is to be understood that with each gripper mechanism, there isto be associated an individual control arrangement such as disclosed anddescribed in connection with the single gripper mechanism GA of Figs. 17to 20,

With the web-feeding mechanism of Figs. 17 to 20 there may be utilizedapparatus for forming the web into containers which are filled andsealed before the webbing is cut to detach the v filled packages, all asdisclosed in the modifications previously described herein; andconversely, it is to be understood the web-feeding arrangements shown inFigs. 1 to 10, and Figs. 11 to 19 may be utilized to cut individualwrappers from the webbing for subsequent use as in a wrapping orpackaging machine. For brevity in the appended claims, the term wrapper,unless inconsistent with the context, is used to comprehend wrappers,labels, or the like, which are applied either before or after theirseverance from the we What I claim is:

1. The method of feeding a plurality of webs having substantiallyregularly spaced control elements thereon which comprises intermittentlyand concurrently feeding the webs, while the webs are at rest betweensuccessive feeding movements inspecting the positions of controlelements thereon, and varying the extents of feed of the individual websfor successive feeding movements thereof each in accordance with theposition of the previously observed control element thereof.

2. In web-feeding apparatus comprising reciprocatory web-feedingstructure, the method of operation which comprises effectingintermittent concurrent feed of a plurality of webs by successivemovements of said structure in onedirection, between said successivemovements of said structure inspecting the positions of control elementson the webs, and predetermining the extents of feed of the individualwebs for each movement of said structure in said direction in accordancewith the previously observed control elements on the respective webs.

3. In web-feeding apparatus comprising reciprocatory web-feedingstructure, themethod of operation which comprises efiecting intermittentconcurrent ieed of a plurality of webs by successive movements of saidstructure in one direction, between said successive movements of saidstructure inspecting the positions of control elements on the webs, andreleasing the webs individually from said structure in each of saidsuccessive movements thereof each in accordance with the position of thepreviously observed control element thereon.

4. In. web-feeding apparatus comprising reciprocatory web-feedingstructure, the method of operation which comprises effectingintermittent concurrent feed of a plurality of webs by successivemovements of said structure in one direction, between said successivemovements of said structure inspecting the positions of control elementson the webs, and varying the times of connection of said structure tothe different webs during each of its movements in reverse direction inaccordance with the positions of the observed control elements thereon.

5. In web-feeding apparatus comprising reciprocatory web-feedingstructures, the method of operation which comprises effecting intermittent concurrent feed of a plurality of webs by successive movements ofsaid structures in forward direction, while said webs are at restinspecting the positions of control elements there on, and varying theextents of concurrent forward movements of said structures in accordancewith the previously observed control elements on their respective webs.

6. In the art of making wrappers from webs having substantiallyregularly spaced control elements thereon, the method which comprisesintermittently and concurrently feeding the webs toward a web-cuttingstation, at said station concurrently cutting the webs while they are atrest between successive feeding movements thereof, inspecting the webswhile at rest between successive feeding movements thereof to detectchanges in the positions of successively observed control elements.progressively increasing the extent of feed of each web in successivefeeding movements thereof after a control element thereon has beenobserved at one predetermined position and until a control elementthereon is observed at another predetermined position, and thereafterprogressively decreasing the extent of feed of each web in successivefeeding movements thereof until a control element thereon is observed atsaid first predetermined position.

7. Mechanism for feeding webs each having thereon substantiallyregularly spaced control elements comprising feeding means for each ofsaid webs, means cyclically operative intermittently to effectconcurrent operation of the several web-feeding means, and registrationdetectors responsive to control elements upon the different webs forpredetermining the extents to which each individual web is advancedduring successive cycles of said means.

8. Mechanism for feeding webs each having thereon substantiallyregularly spaced control elements comprising web-clamping devices forthe individual webs, cyclically operated means for reciprocating saiddevices in unison to effect intermittent feed of the webs, andregistration detectors responsive to control elements upon differentwebs for controlling the timing of the individual web-clamping devicesto predetermine the extents to which the individual webs are advancedduring successive reciprocations of said devices.

9. Mechanism for feeding webs each having thereon substantiallyregularly spaced control elementscomprising web-clamping devices for theindividual webs, cyclically operated means for reciprocating saiddevices in unison to effect intermittent feed of the webs, andregistration detectors responsive to control elements upon differentwebs for individually varying the extents of movement of said devicesduring successive cycles of reciprocation thereof.

10. Mechanism for feeding a web having thereon substantially regularlyspaced control elements comprising a web-clamping device, means foreffecting reciprocation of said device including a rotatable barrel camand a member engaging the periphery thereof, means for effectingclamping and release of the web by the jaws of said device including arotatable barrel cam and a member engaging the periphery thereof, and adetector responsive to said control elements for varying the position ofone of said cams with respect to its associated member along the axis ofrotation of the cam. 4

11. Mechanism for feeding a web having thereon substantially regularlyspaced control elements comprising web-clamping device, mechanism forreciprocating said device, means for effecting operation of said devicealternately to clamp and release the web including a rotatable barrelcam and a member engaging the periphery thereof, and a detectorresponsive to said control elements for varying the position of said camwith respect to said member along the axis of rotation of said cam.

12. Mechanism for feeding a web having thereon substantially regularlyspaced control elements comprising a web-clamping device, means foreffecting reciprocation of said device comprising a rotatable barrel camand a member engaging the periphery thereof, mechanism for effectingoperation of said device to clamp or release the web, and a, detectorresponsive to said control elements for varying the axial position ofsaid cam with respect to said member to change the extent ofreciprocation of said device.

13. Apparatus for making wrappers from a web having thereonsubstantially regularly spaced control elements comprising aweb-clamping device including relatively movable gripper members, aweb-cutting device including relatively movable cutting members,mechanism for reciprocating said web-clamping device intermittently tofeed the web toward said'web-cutting device, a common operatingmechanism for said devices effecting web-clamping movement of saidgripper members concurrently with separation of said cutting members andweb-releasing movement of said gripper members concurrently withwebsevering movement of said cutting members, a detector responsive tosaid control elements, and means controlled in accordance with theresponses of said detector when said web is at rest for controlling oneoi said mechanisms to vary the extents to which the web is fed bysuccessive reciprocations of the web-clamping device.

14. Apparatus for making wrappers from a web having thereonsubstantially regularly spaced control elements comprising aweb-clamping device including relatively movable gripper members, aweb-cutting device including relatively movable cutting members,mechanism for reciprocating said web-clamping device in a path ofconstant length intermittently to feed the web toward said web-cuttingdevice, mechanism for eflecting operation of said devices in fixed timedrelation to each other during the successive cycles of reciprocation ofsaid web-clamping device, a detector responsive to said controlelements, and means controlled in accordance with the responses of saiddetector when said web isat rest for varying the timing of saidsecond-named mechanism with respect to the reciprocation of saidwebclamping device in the successive cycles thereof.

15. Mechanism for making wrappers from a web having thereonsubstantially regularly spaced control elements comprising aweb-clamping device, a web-cutting device, means for reciprocating saidweb-clamping device intermittently to feed the web toward saidweb-cuttingdevice, means for effecting operation of said web-cutting andweb-clamping devices at fixed times in successive cycles ofreciprocation of said web-clamping device, a detector responsive to saidcontrol elements, and means controlled in accordance with the responsesof said detector when said web is at rest to vary the stroke of saidweb-clamping device in its successive cycles of reciprocation.

16. Mechanism for making wrappers from webs having thereon substantiallyregularly spaced control elements comprising web-clamping devices forthe individual webs, web-cutting devices for the individual webs, meansfor reciprocating said web-clamping devices in unison intermittently tofeed the webs toward their respective web-cutting devices, and detectorsresponsive to control elements of the individual webs for controllingthe times of operation of the clamping and cutting devices of theindividual webs in each cycle of reciprocation of said cutting devices.

DANIEL E. MAXFIELD.

CERTIFICATE OF CORRECTION.

mam No. 2,199,708. May 7, 191m.

DANIEL E. 'MAXFIELD.

It is hereby certified that error appears in the printed specificationof the above numbered patent requiring correction as follows: Page Lfirst column, line 11, for suffix A read "suffix "A"--; page 9, secondcolumn, line 58, claim ii after the word said insert -the relativelymovable members of said--; and that the said Letters Patent should beread with this correction therein that the same may conform to therecord of the case in the Patent Office.

Signed and sealed this 11th day of March, A. D. 19t1.

. Henry Van Arsdale, (Seal) Acting Commissioner of Patents.

